EPUB Reader
Read EPUB e-books with interactive word lookup, per-block translation, and progress that persists across sessions.
Getting Started
Upload an EPUB
- Navigate to Reading → EPUB Reader in the menu
- Drag & drop an
.epubfile onto the upload zone, or click Browse to select one from your device - The cover image appears — tap it to start reading
The file is stored locally in your browser (IndexedDB). Next time you visit, it will load automatically and you'll resume from where you left off.
Navigation
| Feature | How |
|---|---|
| Next/Previous chapter | Use the buttons at the top of the sidebar, or click chapter titles in the table of contents |
| Collapse/expand sidebar | Click the ≡ toggle in the top-right corner of the title bar |
| Close the book | Click ✕ Close in the title bar to return to the upload screen |
| Page turn within a chapter | Use ← / → keys or the page controls at the bottom of the reader |
| Table of contents | Nested TOC items are indented for easy navigation |
Reading Features
- Click any word to look up its dictionary definition, pronunciation, and example sentences
- Per-block translation — Click the
Languagesicon in the page nav bar to translate the current page's visible blocks - Auto-translate on page turn — When translation is enabled, the next page's content is translated automatically
- Inline translation display — On wide screens, original and translation appear side by side. On narrow screens, translation appears below each block.
Supported Formats
.epub— Standard EPUB files (EPUB 2 and EPUB 3).epubwith furigana/ruby — Japanese books with ruby annotations are stripped of furigana, keeping only the base kanji text- Vertical text — Books with CSS
writing-mode: vertical-rlare detected (display uses standard horizontal layout for readability)
Progress Saving
Your reading position is saved automatically in your browser:
- Current chapter is saved when you switch chapters
- Text anchor (the first ~40 characters of the visible page) is saved when you turn pages
- On your next visit, the book reloads and scrolls to the correct position
Note: Progress is stored locally (IndexedDB), not synced to the cloud. Only one book is stored at a time — uploading a new one replaces the previous.
Getting Free EPUBs
- Project Gutenberg — 70,000+ free ebooks in many languages (look for " EPUB with images" or " Plain Text UTF-8")
- Aozora Bunko (青空文庫) — Japanese literature, public domain
- Wikisource — Public domain texts in many languages, downloadable as EPUB
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